Effect of IL-18 injection to donors before BMT on the biochemical indices of acute GVHD and donor T-cell proliferation.

B6 mice underwent transplantation as in Figure 1. Sera from the recipient animals (n = 3 mice/group) were obtained on day 7 after BMT and analyzed as described in “Materials and methods.” (A) Serum LPS levels are reduced in the recipients of IL-18–treated donor cells. Controls (▪) versus IL-18 allo recipients (░); *P < .05. Results from 1 of 2 similar experiments are shown. (B) Serum TNF-α levels are reduced. Controls (▪) versus IL-18–treated recipients (░); **P < .01. Data from 1 of 2 similar experiments are shown. (C) B6 Ly5.2 (CD45.1⁺) recipient mice underwent transplantation as in Figure 1. Splenocytes were harvested from the recipients at each time point as shown (n = 4/per group) and labeled with anti-CD3⁺ PE and anti-CD45.1⁺ FITC. The number of donor T cells (CD45.1⁻CD3⁺) was determined (▴, allo+control vs ●, allo+IL-18) at various time points, on days 7 and 14 after BMT. Recipients of syngeneic BM transplants (▪) demonstrated lower numbers of donor T cells at all time points. Data from 1 of 3 representative experiments are shown. Error bars represent standard error.